656879 has 4 divisors (see below), whose sum is σ = 679560. Its totient is φ = 634200.

The previous prime is 656839. The next prime is 656891. The reversal of 656879 is 978656.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656879 is a prime.

It is an Ulam number.

It is a Duffinian number.

Its product of digits (90720) is a multiple of the sum of its prime divisors (22680).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11297 + ... + 11354.

It is an arithmetic number, because the mean of its divisors is an integer number (169890).

2⁶⁵⁶⁸⁷⁹ is an apocalyptic number.

656879 is a deficient number, since it is larger than the sum of its proper divisors (22681).

656879 is a wasteful number, since it uses less digits than its factorization.

656879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22680.

The product of its digits is 90720, while the sum is 41.

The square root of 656879 is about 810.4807215474. The cubic root of 656879 is about 86.9284213296.

The spelling of 656879 in words is "six hundred fifty-six thousand, eight hundred seventy-nine".